DYNAUDIO CONNECT API (preliminary)
This document describes the Dynaudio - Connect API. This API gives control and feedback of devices linked with the Connect (e.g. Xeo 4/6, Focus-XD).
This document is mostly accurate. However, I might have mixed up states (on/off).
Contents
1. Overview
All command and feedback messages have the following structure:
0xFF 0x55 0x'payload size (PS)' [payload of PS bytes] 0x'checksum'
2. Control
The API allows for control of the volume level and the functions mute, input, and power. The payload size (PS) has a length of 5 bytes.
Most commands carry a status value (SV). This value carries current zone (Z) and input (I) information. This byte is calculated as follows: 0x'I'*16+0x'Z'.
The following commands can be identified:
| type | Command Code (CC) | Command Value (CV) | payload structure | payload example |
|---|---|---|---|---|
| volume | 0x13 / 0x14 | 0x00 - 0x11 | 0x2F 0xA0 0x'CC' 0x'CV' 0x'SV' | 0x2F 0xA0 0x13 0x04 0x42 |
| mute (off/on) | 0x12 | 0x00 / 0x01 | 0x2F 0xA0 0x'CC' 0x'CV' 0x'SV' | 0x2F 0xA0 0x12 0x01 0x42 |
| input | 0x15 | 0x01 - 0x07 | 0x2F 0xA0 0x'CC' 0x'CV' 0x'SV' | 0x2F 0xA0 0x15 0x04 0x42 |
| power on | 0x01 | 0x00 | 0x2F 0xA0 0x01 0x'CV' 0xF'Z' | 0x2F 0xA0 0x01 0x00 0xF2 |
| power off | 0x02 | 0x00 | 0x2F 0xA0 0x02 0x'CV' 0xF'Z' | 0x2F 0xA0 0x02 0x00 0xF2 |
Notice that volume has two commands codes. The CC for volume up is 0x13 and for volume down 0x14.
The Dynaudio Connect has 7 inputs. Their 'Command Values' are as follows:
| input type | Command Value (CV) |
|---|---|
| Minijack | 0x01 |
| Line | 0x02 |
| Optical | 0x03 |
| Coax | 0x04 |
| USB | 0x05 |
| Bluetooth | 0x06 |
| Stream | 0x07 |
Devices linked with the Dynaudio Connect can be set to one of three zones. Their numeric values are:
| zone colour | zone value |
|---|---|
| Red | 0x01 |
| Green | 0x02 |
| Blue | 0x03 |
2.1. Shortcuts
Not all that is specified is necessary. While volume commands have a specific command code for volume up and down, when specifying absolute volume commands (is there another way?), this distinction can be ignored.
The status value supplied with most commands is only partially processed. It is necessary to specify the correct zone. However, the input part of the status value is ignored.
3. Feedback
Feedback is slightly different and carries a payload of 8 bytes instead of 5. A number of examples follow:
| type | Command Code (CC) | Command Value (CV) | payload structure | payload example |
|---|---|---|---|---|
| volume | 0x04 / 0x05 | 0x00 - 0x11 | 0x2E 0xA0 0x'CC' 0x'CV' 0x'SV' 0x00 0x00 0xD9 | 0x2E 0xA0 0x05 0x04 0x42 0x00 0x00 0xD9 |
| mute | 0x03 | 0x00 / 0x01 | 0x2E 0xA0 0x'CC' 0x'CV' 0x'SV' 0x00 0x00 0xD9 | 0x2F 0xA0 0x12 0x01 0x42 0x00 0x00 0xD9 |
| input | 0x?? | ?? | ?? | ?? |
| power on | 0x01 | 0x00 | 0x2E 0xA0 0x01 0x'CV' 0x'SV' 0x00 0x00 0xD9 | 0x2F 0xA0 0x01 0x00 0xF2 0x00 0x00 0xD9 |
| power off | 0x02 | 0x00 | 0x2E 0xA0 0x02 0x'CV' 0x'SV' 0x00 0x00 0xD9 | 0x2F 0xA0 0x02 0x00 0xF2 0x00 0x00 0xD9 |
Notice again the differential CC for volume up and down. While the feedback on input changes is still uncertain, it can be extracted from other commands, notice the SV on the commands.
3.1 Shortcuts
idem to 2.1
4. Checksum
The checksum can be calculated as follows:
ROUNDUP(SUM(payload)/255)*255-SUM(payload)-([Payload N]-ROUNDUP(SUM(payload)/255))
If the result is negative add 256 or alternatively extract the 8 least significant bits.
5. Connection
Connect through port 1901. Only one connection is allowed at a time.
6. Questions and Requests
Questions and request can be submitted via GitHub.
For an example in C check this file.
7. Glossary
- PS - Payload Size [in bytes]
- Z - current Zone
- I - Input number
- CC - Command Code
- CV - Command Value
- SV - Status Value [zone and input]
- Ch - Checksum